How do i play a video through an object on blender 2.8?
How do i play a video through an object on blender 2.8? does doing this work the same way as of in the stable version of
  blender 2.79?


Yes. Import >Images as Planes.

You can also drag and drop as an active empty to bench it.


  And another thing is that the video i am wanting to add to a plain is
  2 minutes and 44 seconds long is there a duration limit on putting a
  video on an object?


To my knowledge, no. However, it seems to play slower with large files. my best experience has been when using Eevee. 3 minutes should play fine.

Blender's 2.8 latest build supports this feature.
https://builder.blender.org/download/

Plays butter smooth on my PC.

Import images as planes is an add-on

To enable it, go to Edit -> Preferences -> Add-ons.